Experts are pushing back on recent claims by President Donald Trump that Iran was just weeks away from obtaining a nuclear weapon before the United States military action late last month.Trump has said in recent days that Iran would have had a nuclear weapon within two weeks if the U.S. had not launched aerial strikes. But reporting from NBC News and statements from nuclear experts suggest the president’s timeline "is not true.""Before U.S.-Israeli airstrikes in June, Iran was days away from having enough fissile material for multiple nuclear weapons, according to U.S. intelligence agencies and the U.N. International Atomic Energy Agency," according to the report. However, producing an actual nuclear weapon would require "designing, manufacturing, and testing" a warhead capable of being mounted on a ballistic missile – a process experts told NBC News would likely take months or even a year.U.S. intelligence agencies have maintained that Iran has not decided to revive its weapons program, which was halted in 2003.“It would be inaccurate to suggest Iran was two weeks away from having a nuclear weapon before the U.S. and Israel launched the current air war on Feb. 28 because of the damage done by the June strikes, according to assessments from the IAEA and independent nuclear experts,” NBC News reported Monday.Iran does retain significant nuclear material, the outlet added. “Before the June airstrikes, the IAEA said Iran had 972 pounds of uranium enriched to a level of 60%," it said. "If it were enriched further to about 90%, that would be enough fissile material for roughly a dozen atomic bombs.”